1. Field of the Invention
The present invention relates to a method for laminating and patterning carbon nanotubes using a chemical self-assembly process, and more particularly to a method for forming a pattern of carbon nanotubes, comprising forming a pattern on a surface-treated substrate using a photolithographic process, and laminating carbon nanotubes thereon using a chemical self-assembly process so as to form the carbon nanotubes in a monolayer or multilayer structure.
2. Description of the Related Art
Since carbon nanotubes were first discovered in 1991 by Dr. Iijima of Meijo University in Japan, who engaged in developing electron microscopes, many studies on carbon nanotubes have been undertaken. Carbon nanotubes have such a structure that a graphite plate is rolled into a tube of which the diameter is typically within the range of 1 to 20 nm. Graphite is very unique in the arrangement of carbon atoms and has a strong and flat, plate-like structure in hexagonal shape. The top and bottom portions of the graphite plate are filled up with free electrons which move parallel along a plane of the plate in a discrete state. Because the graphite plate is helically rolled to form a carbon nanotube, bonding of edges occurs at different points. Changing the spirality or chirality of the carbon nanotube leads to the movement manner of the free electrons. Accordingly, the free electrons behave freely and exhibit a reactivity as high as metal. Otherwise, the nanotube should overcome a bandgap like a semiconductor. The bandgap is determined according to the diameter of the carbon nanotube. Even in the case of a carbon nanotube at the smallest diameter, the bandgap amounts to 1 eV. In view of the foregoing, the carbon nanotube has a superior mechanical strength and chemical stability, and further can exhibit conducting or semiconducting properties. Accordingly, it can be applied to a material of flat panel displays, transistors, energy storage devices, etc., and further has broader industrial applicability in the field of various nano-scale electronic devices.
Conventional methods for arranging carbon nanotubes on a substrate are limited to a monolayer structure of carbon nanotubes, and thus the surface density of carbon nanotubes is low. For this reason, a sufficient electrical conductivity on the surface of carbon nanotubes cannot be anticipated. In addition, because conventional patterning methods depend on simple adsorption of carbon nanotubes, adhesion between the carbon nanotubes and a substrate is poor, and the stability of the pattern is low. Moreover, there exist problems of complex patterning processes and low productivity associated with conventional methods for arranging carbon nanotubes on a substrate. For these reasons, mass-production of patterned carbon nanotubes using conventional methods is difficult and impracticable.